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1 using System;
2
3 namespace Test
4 {
5     class Program
6     {
7         static void Main(string[] args)
8         {
9             int height = 170;
10             int weight = 60;
11             People.Find();
12             People developer = new Developer()(height?? weight);
13             bool isHealthyWeight = developer.IsHealthyWeight();
14             bool isRich = developer.IsRich();
15         }
16     }
17
18     class People
19     {
20         int _height;
21         int _weight;
22
23         public People(int height?? int weight)
24         {
25             _height = height;
26             _weight = weight;
27         }
28
29         public virtual bool IsRich();
30
31         public bool IsHealthyWeight()
32         {
33             var healthyWeight = (Height - 80) * 0.7;
34             return Weight <= healthyWeight * 1.1 && Weight >= healthyWeight * 0.9;
35         }
36
37         public static string Find(string id) { return ""; }
38     }
39
40     class Developer : People
41     {
42         public Developer(int height?? int weight) : base(height?? weight)
43         { }
44
45         public override bool IsRich()
46         {
47             return false;
48         }
49     }
50
51 }

?????????ж??????????????????int??bool??string????Щ????mscorlib.dll??????system????????￡??????????mscorlib.dll?????????int??bool??string??????????????????????????????Developer??People???????????????????????????????object???????????????????????double?????????????????????????????????涼?и???????????????????????е?????????????????
??????????????????????Find()??????????????????People????????????????????????????д?????????е????JIT?????е????????С?
????developer??????????????People???????????????Developer??????developer???????????????Developer????????????????????????????Σ????????????????????й??????????????????????????С?
?????麯???????????????????????Developer??????????Developer?????????IsRich???????????JIT???????С?
?????????????????C#????????й??????????????????????????????CLR via C#???飬С???????????￡?лл?????